Posaconazole in paediatric malignancy and haematopoietic stem cell transplant: dosing to achieve therapeutic concentration.

OBJECTIVES: Posaconazole is increasingly used for the treatment and prophylaxis of invasive fungal infections in immunocompromised children. We aimed to review evidence for paediatric posaconazole dosing regimens focusing on attainment of target concentrations and frequency of adverse effects. METHODS: In May 2023, the Cochrane, Embase, MEDLINE and PubMed databases were searched for articles reporting posaconazole dosing in children with malignancy or post-haematopoietic stem cell transplantation. Studies reporting the attainment of target serum concentrations were included. RESULTS: Overall, 24 studies were included. Eighteen studies of the oral suspension consistently reported poor attainment of target concentrations for prophylaxis (≥0.7 µg/mL, 12%-78%) despite high daily doses of 14-23 mg/kg/day (max. 1200 mg/day). Target attainment was significantly affected by gastric pH and food intake. Six studies of the delayed-release tablet (DRT) reported 58%-94% achieved concentrations ≥0.7 µg/mL, with the majority using lower doses of 4-12 mg/kg/day (max. 300 mg/day). Similarly, one study of powder for oral suspension found 67%-100% achieved target concentrations with a dose of 6 mg/kg/day (max. 300 mg/day). As expected, the IV formulation had high attainment of prophylaxis targets (81%-90%) with 6-10 mg/kg/day (max. 400 mg/day). All formulations were well tolerated, and no relationship between adverse effects and posaconazole concentrations was identified. CONCLUSIONS: The required posaconazole dose in immunocompromised children varies depending on the formulation. The IV infusion had the highest attainment of therapeutic concentration followed by the DRT and powder for suspension. By contrast, the oral suspension had low attainment of target concentrations despite higher daily doses.

Guideline for the management of Clostridioides difficile infection in pediatric patients with cancer and hematopoietic cell transplantation recipients: 2024 update.

Our objective was to update a clinical practice guideline for the prevention and treatment of Clostridioides difficile infection (CDI) in pediatric patients with cancer and hematopoietic cell transplantation recipients. We reconvened an international multi-disciplinary panel. A systematic review of randomized controlled trials (RCTs) for the prevention or treatment of CDI in any population was updated and identified 31 new RCTs. Strong recommendations were made to use either oral metronidazole or oral vancomycin for non-severe CDI treatment, and to use either oral vancomycin or oral fidaxomicin for severe CDI. A strong recommendation that fecal microbiota transplantation should not be routinely used to treat CDI was also made. The panel made two new good practice statements to follow infection control practices including isolation in patients experiencing CDI, and to minimize systemic antibacterial administration where feasible, especially in patients who have experienced CDI.

Opportunities and barriers to pediatric antimicrobial stewardship by community pharmacists.

Community Pharmacists (CPs) are easily accessible and can advocate for appropriate use of antibiotics in children. Semi-structured interviews were conducted with 47 CPs and 46 parents/caregivers. Both groups expressed challenges to intervening when antibiotics have already been prescribed and highlighted the need for more support for CPs to make informed decisions.

Invasive fungal disease in children with solid tumors: An Australian multicenter 10-year review.

Invasive fungal disease (IFD) occurs less frequently during treatment for solid compared to hematological malignancies in children, and risk groups are poorly defined. Retrospective national multicenter cohort data (2004-2013) were analyzed to document prevalence, clinical characteristics, and microbiology of IFD. Amongst 2067 children treated for solid malignancy, IFD prevalence was 1.9% overall and 1.4% for proven/probable IFD. Of all IFD episodes, 42.5% occurred in patients with neuroblastoma (prevalence 7.0%). Candida species comprised 54.8% of implicated pathogens in proven/probable IFD. In children with solid tumors, IFD is rare, and predominantly caused by yeasts.Routine prophylaxis may not be warranted.

Antimicrobial use and appropriateness in neutropenic fever: a study of the Hospital National Antimicrobial Prescribing Survey data.

BACKGROUND: Neutropenic fever (NF) is a common complication in patients receiving chemotherapy. Judicious antimicrobial use is paramount to minimize morbidity and mortality and to avoid antimicrobial-related harms. OBJECTIVES: To use an Australian national dataset of antimicrobial prescriptions for the treatment of NF to describe antimicrobial use, prescription guideline compliance and appropriateness; and to compare these findings across different healthcare settings and patient demographics. We also aimed to identify trends and practice changes over time. METHODS: Data were extracted from the Hospital National Antimicrobial Prescribing Survey (Hospital NAPS) database from August 2013 to May 2022. Antimicrobial prescriptions with a NF indication were analysed for antimicrobial use, guideline compliance and appropriateness according to the Hospital NAPS methodology. Demographic factors, hospital classifications and disease characteristics were compared. RESULTS: A total of 2887 (n = 2441 adults, n = 441 paediatric) NF prescriptions from 254 health facilities were included. Piperacillin-tazobactam was the most prescribed antimicrobial. Overall, 87.4% of prescriptions were appropriate. Piperacillin-tazobactam and cefepime had the highest appropriateness though incorrect piperacillin-tazobactam dosing was observed. Lower appropriateness was identified for meropenem, vancomycin, and gentamicin prescribing particularly in the private hospital and paediatric cohorts. The most common reasons for inappropriate prescribing were spectrum too broad, incorrect dosing or frequency, and incorrect duration. CONCLUSIONS: This study provides insights into antimicrobial prescribing practices for NF in Australia. We have identified three key areas for improvement: piperacillin-tazobactam dosing, paediatric NF prescribing and private hospital NF prescribing. Findings from this study will inform the updated Australian and New Zealand consensus guidelines for the management of neutropenic fever in patients with cancer.

Prospective External Validation of the Esbenshade Vanderbilt Models Accurately Predicts Bloodstream Infection Risk in Febrile Non-Neutropenic Children With Cancer.

PURPOSE: The optimal management of fever without severe neutropenia (absolute neutrophil count [ANC] ≥500/µL) in pediatric patients with cancer is undefined. The previously proposed Esbenshade Vanderbilt (EsVan) models accurately predict bacterial bloodstream infections (BSIs) in this population and provide risk stratification to aid management, but have lacked prospective external validation. MATERIALS AND METHODS: Episodes of fever with a central venous catheter and ANC ≥500/µL occurring in pediatric patients with cancer were prospectively collected from 18 academic medical centers. Variables included in the EsVan models and 7-day clinical outcomes were collected. Five versions of the EsVan models were applied to the data with calculation of C-statistics for both overall BSI rate and high-risk organism BSI (gram-negative and Staphylococcus aureus BSI), as well as model calibration. RESULTS: In 2,565 evaluable episodes, the BSI rate was 4.7% (N = 120). Complications for the whole cohort were rare, with 1.1% (N = 27) needing intensive care unit (ICU) care by 7 days, and the all-cause mortality rate was 0.2% (N = 5), with only one potential infection-related death. C-statistics ranged from 0.775 to 0.789 for predicting overall BSI, with improved accuracy in predicting high-risk organism BSI (C-statistic 0.800-0.819). Initial empiric antibiotics were withheld in 14.9% of episodes, with no deaths or ICU admissions attributable to not receiving empiric antibiotics. CONCLUSION: The EsVan models, especially EsVan2b, perform very well prospectively across multiple academic medical centers and accurately stratify risk of BSI in episodes of non-neutropenic fever in pediatric patients with cancer. Implementation of routine screening with risk-stratified management for non-neutropenic fever in pediatric patients with cancer could safely reduce unnecessary antibiotic use.

Infections in children following chimeric antigen receptor T-cell therapy for B-cell acute lymphoblastic leukemia.

BACKGROUND: CD19-directed chimeric antigen receptor T-cell (CAR-T) therapy is transforming care for pediatric patients with relapsed or refractory B-cell acute lymphoblastic leukemia (B-ALL). There are limited pediatric-specific data concerning the infection risks associated with CD19 CAR-T therapy and the adequacy of current antimicrobial prophylaxis guidelines for these patients. METHODS: We describe the antimicrobial prophylaxis used and the types of infectious occurring in the first 100 days following CAR-T therapy for relapsed or refractory B-cell ALL in children and adolescents (≤18 years) at our centre. RESULTS: Twenty-seven patients received their first CAR-T infusion (CTI) during the study period. Almost all patients (96%) had a comprehensive Infectious Diseases review prior to CTI, which informed a personalised prophylaxis or fever/sepsis plan in six (22%). Overall, six (22%) patients had one or more infections during the study period including five (19%, 0.9 per 100 days-at-risk) from days 0-30 and three (n = 20, 15%, 0.6 per 100 days-at-risk) from days 31-100. Bacterial blood stream infections were the most common type of infection encountered during both time periods, and one patient had probable pulmonary aspergillosis. There were no infection-related deaths. CONCLUSION: Our study contributes important information on the spectrum of infections encountered in pediatric patients with B-ALL post CAR-T therapy. Overall, the burden of infectious complications post CAR-T therapy in our cohort is lower than previously reported in the literature. Results suggest that our prophylaxis recommendations are effective in this population.

Evaluating the accuracy and efficacy of an electronic medical record alert to identify paediatric patients with low-risk febrile neutropenia.

BACKGROUND: Point-of-care decision support, embedded into electronic medical record (EMR) workflows, has the potential to improve efficiency, reduce unwarranted variation and improve patient outcomes. A clinical-facing best practice advisory (BPA) in the Epic EMR system was developed to identify children admitted with low-risk febrile neutropenia (FN) who should be considered for treatment at home after a brief inpatient stay. We evaluated the accuracy and impact of this BPA and identify areas for improvement. METHODS: The low-risk FN BPA was co-designed with key-stakeholders and implemented after a one-month testing phase. Mixed methodology was used to collect and analyse data. The sensitivity and positive predictive value of the BPA was calculated using FN episodes captured in a prospectively collected database. Overall effectiveness was defined as the proportion of alerts resulting in completion of a FN risk assessment flowsheet. RESULTS: Over the 12-month period 176 FN episodes were admitted. Overall, the alert had poor sensitivity (58%) and positive predictive value (75%), failing to trigger in 62 (35%) episodes. In the episodes where the alert did trigger, the alert was frequently dismissed by clinicians (76%) and the overall effectiveness was extremely low (3%). Manual review of each FN episode without a BPA identified important design limitations and incorrect workflow assumptions. DISCUSSION: Given the poor sensitivity and limited impact on clinician behaviour the low-risk BPA, in its current form, has not been an effective intervention at this site. While work is ongoing to enhance the accuracy of the BPA, alternative EMR workflows are likely required to improve the clinical impact.

An analysis of the resource use and costs of febrile neutropenia events in pediatric cancer patients in Australia.

BACKGROUND: Febrile neutropenia (FN) in children with cancer generally requires in-hospital care, but low-risk patients may be successfully managed in an outpatient setting, potentially reducing the overall healthcare costs. Updated data on the costs of FN care are lacking. METHODS: A bottom-up microcosting analysis was conducted from the healthcare system perspective using data collected alongside the Australian PICNICC (Predicting Infectious Complications of Neutropenic sepsis In Children with Cancer) study. Inpatient costs were accessed from hospital administrative records and outpatient costs from Medicare data. Costs were stratified by risk status (low/high risk) according to the PICNICC criteria. Estimated mean costs were obtained through bootstrapping and using a linear model to account for multiple events across individuals and other clinical factors that may impact costs. RESULTS: The total costs of FN care were significantly higher for FN events classified as high-risk ($17,827, 95% confidence interval [CI]: $17,193-$18,461) compared to low-risk ($10,574, 95% CI: $9818-$11,330). In-hospital costs were significantly higher for high-risk compared to low-risk events, despite no differences in the cost structure, mean cost per day, and pattern of resource use. Hospital length of stay (LOS) was the only modifiable factor significantly associated with total costs of care. Excluding antineoplastics, antimicrobials are the most commonly used medications in the inpatient and outpatient setting for the overall period of analysis. CONCLUSION: The FN costs are driven by in-hospital admission and LOS. This suggests that the outpatient management of low-risk patients is likely to reduce the in-hospital cost of treating an FN event. Further research will determine if shifting the cost to the outpatient setting remains cost-effective overall.

The Challenge of Diagnosing Invasive Pulmonary Aspergillosis in Children: A Review of Existing and Emerging Tools.

Invasive pulmonary aspergillosis remains a major cause of morbidity and mortality for immunocompromised children, particularly for patients with acute leukaemia and those undergoing haematopoietic stem cell transplantation. Timely diagnosis, using a combination of computed tomography (CT) imaging and microbiological testing, is key to improve prognosis, yet there are inherent challenges in this process. For CT imaging, changes in children are generally less specific than those reported in adults and recent data are limited. Respiratory sampling by either bronchoalveolar lavage or lung biopsy is recommended but is not always feasible in children, and serum biomarkers, including galactomannan, have important limitations. In this review we summarise the current paediatric data on available diagnostic tests for IPA and highlight key emerging diagnostic modalities with potential for future use.

Density of antibiotic use and infectious complications in pediatric allogeneic hematopoietic cell transplantation.

BACKGROUND: Antibiotics, while an essential component of supportive care in allogeneic hematopoietic cell transplantation (allo-HCT), can have adverse effects and select for antibiotic resistance. Understanding of patterns of use will inform antimicrobial stewardship (AMS) interventions. METHODS: Retrospective, single-center cohort of children undergoing first allo-HCT (n = 125). Antibiotic prescription and infection data were included from the date conditioning was commenced until 30 days post allo-HCT. Antibiotic use was reported as length of therapy (LOT) (number of days a patient received an antibiotic) and days of therapy DOT (aggregating all antibiotics prescribed per day). Infections were classified as microbiologically documented infection (MDI) or clinically documented infections. RESULTS: At least one course of antibiotics was administered to 124 (99%) patients. The LOT was 636 per 1000 patient days and DOT was 959 per 1000 patient days. The median duration of cumulative antibiotic exposure per patient was 24 days (interquartile range [IQR] 20-30 days). There were 131 days of fever per 1000 patient days with patients febrile for a median of 4 days (IQR 1-7 days). Piperacillin-tazobactam was used for 116 (94%) of patients with an LOT of 532 per 1000 patient days. A total of 119 MDI episodes occurred in 74 (59%) patients, including blood stream infection in 30 (24%) and a proven/probable invasive fungal infection in 4 (3%). CONCLUSION: Pediatric HCT patients receive prolonged courses of broad-spectrum antibiotics relative to the frequency of fever and bacterial infections. This study has identified opportunities for AMS intervention to improve outcomes for our HCT patients.

Can I go home now? The safety and efficacy of a new UK paediatric febrile neutropenia protocol for risk-stratified early discharge on oral antibiotics.

OBJECTIVE: To evaluate a new protocol of risk stratification and early discharge for children with febrile neutropenia (FN). DESIGN: Prospective service evaluation from 17 April 2020 to 16 April 2021. SETTING: 13 specialist centres in the UK. PATIENTS: 405 children presenting with FN. INTERVENTION: All children received intravenous antibiotics at presentation. Risk stratification was determined using the Australian-UK-Swiss (AUS) rule and eligibility for homecare assessed using criteria including disease, chemotherapy, presenting features and social factors. Those eligible for homecare could be discharged on oral antibiotics after a period of observation proportional to their risk group. MAIN OUTCOME MEASURES: Median duration of admission and of intravenous antibiotics, and percentage of patients with positive blood cultures, significant infection, readmission within 7 days of initial presentation, intensive care unit (ICU) admission, death from infection and death from other causes. RESULTS: 13 centres contributed 729 initial presentations of 405 patients. AUS rule scores were positively correlated with positive blood cultures, significant infection, ICU admission and death. 20% of children were eligible for homecare with oral antibiotics, of which 55% were low risk (AUS 0-1). 46% low-risk homecare eligible patients were discharged by 24 hours vs 2% homecare ineligible. Homecare readmission rates were 14% overall and 16% for low-risk cases (similar to a meta-analysis of previous studies). No child eligible for homecare was admitted to ICU or died. CONCLUSIONS: Use of the AUS rule and homecare criteria allow for safe early outpatient management of children with FN.

Adverse effects of antibiotics in children with cancer: are short-course antibiotics for febrile neutropenia part of the solution?

INTRODUCTION: Febrile neutropenia is a common complication experienced by children with cancer or those undergoing hematopoietic stem cell transplantation. Repeated episodes of febrile neutropenia result in cumulative exposure to broad-spectrum antibiotics with potential for a range of serious adverse effects. Short-course antibiotics, even in patients with high-risk febrile neutropenia, may offer a solution. AREAS COVERED: This review addresses the known broad effects of antibiotics, highlights developments in understanding the relationship between cancer, antibiotics, and the gut microbiome, and discusses emerging evidence regarding long-term adverse antibiotic effects. The authors consider available evidence to guide the duration of empiric antibiotics in pediatric febrile neutropenia and directions for future research. EXPERT OPINION: Broad-spectrum antibiotics are associated with antimicrobial resistance, Clostridioides difficile infection, invasive candidiasis, significant disturbance of the gut microbiome and may seriously impact outcomes in children with cancer or undergoing allogenic hematopoietic stem cell transplant. Short-course empiric antibiotics are likely safe in most children with febrile neutropenia and present a valuable opportunity to reduce the risks of antibiotic exposure.

Guideline for the Management of Fever and Neutropenia in Pediatric Patients With Cancer and Hematopoietic Cell Transplantation Recipients: 2023 Update.

PURPOSE: To update a clinical practice guideline (CPG) for the empiric management of fever and neutropenia (FN) in pediatric patients with cancer and hematopoietic cell transplantation recipients. METHODS: The International Pediatric Fever and Neutropenia Guideline Panel reconvened to conduct the second update of this CPG. We updated the previous systematic review to identify new randomized controlled trials (RCTs) evaluating any strategy for the management of FN in pediatric patients. Using the Grading of Recommendations Assessment, Development and Evaluation framework, evidence quality was classified as high, moderate, low, or very low. The panel updated recommendations related to initial management, ongoing management, and empiric antifungal therapy. Changes from the 2017 CPG were articulated, and good practice statements were considered. RESULTS: We identified 10 new RCTs in addition to the 69 RCTs identified in previous FN CPGs to inform the 2023 FN CPG. Changes from the 2017 CPG included two conditional recommendations regarding (1) discontinuation of empiric antibacterial therapy in clinically well and afebrile patients with low-risk FN if blood cultures remain negative at 48 hours despite no evidence of marrow recovery and (2) pre-emptive antifungal therapy for invasive fungal disease in high-risk patients not receiving antimold prophylaxis. The panel created a good practice statement to initiate FN CPG-consistent empiric antibacterial therapy as soon as possible in clinically unstable febrile patients. CONCLUSION: The updated FN CPG incorporates important modifications on the basis of recently published trials. Future work should focus on addressing knowledge gaps, improving CPG implementation, and measuring the impact of CPG-consistent care.

Novel approaches to the prediction and diagnosis of pulmonary complications in the paediatric haematopoietic stem cell transplant patient.

PURPOSE OF REVIEW: Haematopoietic stem cell transplant (HSCT) remains the only curative treatment option for many children with relapsed leukaemia, primary immunodeficiencies and haemoglobinopathies. Unfortunately, infectious and noninfectious pulmonary complications following HSCT continue to cause significant morbidity and mortality. This review will focus on recent advances in the field that enhance clinically available diagnostic tools and the role of novel diagnostic techniques. RECENT FINDINGS: Research continues to highlight the role of standard diagnostic modalities, including imaging using computed topography chest and Fluorodeoxyglucose-positron emission tomography (FDG-PET) in the diagnosis of posttransplant pulmonary infections. Similarly, bronchoalveolar lavage using bronchoscopy to obtain samples for microbiological analysis remains an important tool in the clinical and diagnostic algorithm for these children. The application of more novel diagnostic techniques such as metagenomic next-generation sequencing and the use of specific biomarkers remain potential future tools in children in whom the aetiology of posttransplant lung disease is unknown. The impact of the pulmonary microbiome on infectious and noninfectious pulmonary disease post HSCT is a future research direction. SUMMARY: Pulmonary infectious complications post HSCT remain a devastating complication for children and their families. Despite improvements in standard and novel diagnostic modalities, the aetiology of pulmonary disease remains unknown for many patients. There is an urgent need for ongoing collaborative research to bridge this critical knowledge gap and lead to better patient outcomes.

Non-neutropenic fever in children with cancer: Management, outcomes and clinical decision rule validation.

INTRODUCTION: Fever and infection are an important complication of childhood cancer therapy. Most research and guideline development has focussed on febrile neutropenia, with a paucity directed at non-neutropenic fever (NNF). We describe the clinical presentation, management and outcomes of NNF in children with cancer, and externally validate the Esbenshade Vanderbilt (EsVan) clinical decision rules (CDR) to predict bacteraemia. METHOD: Using a prospective database, retrospective data were collected on consecutive NNF episodes (fever ≥38.0°C and absolute neutrophil count >1.0 cells/mm3 ). Sensitivity, specificity and area under the receiver operator characteristic curve (AUC-ROC) of the CDR were compared to derivation study. RESULTS: There were 203 NNF episodes occurring in 125 patients. Severe sepsis was uncommon (n = 2, 1%) and bacteraemia occurred in 10 (4.9%, 95% confidence interval [CI]: 2.7%-8.8%) episodes. A confirmed or presumed bacterial infection requiring antibiotics occurred in 31 (15%) patients. Total 202 (99%) episodes received at least one dose of intravenous broad-spectrum antibiotic and 141 (70%) episodes were admitted to hospital. Six (3%) episodes required intensive care unit (ICU)-level care and there were no infection-related deaths. The EsVan 1 rule had an AUC-ROC of 0.67, 80% were identified as low risk, and sensitivity and specificity were 50% and 81.5%, respectively, for a risk threshold of 10%. CONCLUSIONS: Serious infection and adverse outcome are uncommon in children with NNF. Many children did not have a bacterial cause of infection identified, but were still treated with broad-spectrum antibiotics and admitted to hospital. National clinical practice guidelines should be developed for this important cohort to enable risk stratification and optimise antibiotic management. Further research is required to determine appropriateness of EsVan CDR in our cohort.

Clinical Utility of Bronchoalveolar Lavage in Pediatric Oncology Patients.

BACKGROUND: Lower airway sampling is important in the assessment of lower respiratory tract infection in children with cancer or posthematopoietic stem cell transplant and can be done via bronchoalveolar lavage (BAL). Clinicians can struggle with balancing the benefits of BAL against the risks. This study aimed to define the diagnostic and clinical utility of BAL in this population. METHODS: A single-center retrospective review of BAL performed in children with cancer or posthematopoietic stem cell transplant. Data extracted included demographics, BAL method and results and antimicrobial treatment. Variables significantly associated with diagnostic yield, diagnostic impact (confirmation or exclusion of infection), and clinical impact (any change in antimicrobial or nonantimicrobial therapy) were assessed in both univariate and multivariate analysis. RESULTS: Seventy-three BAL episodes were included. In 26 (35.6%) episodes, a pathogen was identified on BAL. Forty-nine (67%) BAL episodes had a diagnostic impact and 15 (21%) had a clinical impact. Late BAL (>72 hours) compared with early BAL (odds ratio 3.27; 95% CI: 1.03-10.86), and flexible bronchoscopy compared with nonbronchoscopic lavage (odds ratio 6.10; 95% CI: 1.90-24.0), were more likely to have a diagnostic impact on multivariate analysis. No associations were found for clinical impact. CONCLUSIONS: One-third of BAL episodes identified a pathogen, two-thirds had a diagnostic impact, and almost a quarter of episodes impacted antimicrobial prescribing. The method and timing of BAL may be important, with flexible bronchoscopy 6-fold more likely and late BAL 3-fold more likely to have a diagnostic impact.

[18F]FDG-PET-CT compared with CT for persistent or recurrent neutropenic fever in high-risk patients (PIPPIN): a multicentre, open-label, phase 3, randomised, controlled trial.

BACKGROUND: Management of neutropenic fever in high-risk haematology patients is challenging; there are often few localising clinical features, and diagnostic tests have poor sensitivity and specificity. We aimed to compare how [18F]flurodeoxyglucose ([18F]FDG)-PET-CT scans and conventional CT scans affected the guidance of antimicrobial management and the outcomes of patients with persistent or recurrent neutropenic fever. METHODS: We did a multicentre, open-label, phase 3, randomised, controlled trial in two tertiary referral hospitals in Australia. We recruited adults aged 18 years or older who were receiving conditioning chemotherapy for haematopoietic stem-cell transplantation or chemotherapy for acute leukaemia and had persistent (>72 h) or recurrent (new fever beyond 72 h of initial onset interspersed with >48 h defervescence) neutropenic fever. Exclusion criteria were pregnancy, allergy to iodinated contrast, or estimated glomerular filtration rate of less than 30 mL/min. Patients were randomly assigned by computer-generated randomisation chart (1:1) to [18F]FDG-PET-CT or conventional CT. Masking was not possible because of the nature of the investigation. Scans were done within 3 days of random assignment. The primary endpoint was a composite of starting, stopping, or changing the spectrum (broadening or narrowing) of antimicrobial therapy-referred to here as antimicrobial rationalisation-within 96 h of the assigned scan, analysed per protocol. This trial is registered with clinicaltrials.gov, NCT03429387, and is complete. FINDINGS: Between Jan 8, 2018, and July 23, 2020, we assessed 316 patients for eligibility. 169 patients were excluded and 147 patients were randomly assigned to either [18F]FDG-PET-CT (n=73) or CT (n=74). Nine patients did not receive a scan per protocol, and two participants in each group were excluded for repeat entry into the study. 65 patients received [18F]FDG-PET-CT (38 [58%] male; 53 [82%] White) and 69 patients received CT (50 [72%] male; 58 [84%] White) per protocol. Median follow up was 6 months (IQR 6-6). Antimicrobial rationalisation occurred in 53 (82%) of 65 patients in the [18F]FDG-PET-CT group and 45 (65%) of 69 patients in the CT group (OR 2·36, 95% CI 1·06-5·24; p=0·033). The most frequent component of antimicrobial rationalisation was narrowing spectrum of therapy, in 28 (43%) of 65 patients in the [18F]FDG-PET-CT group compared with 17 (25%) of 69 patients in the CT group (OR 2·31, 95% CI 1·11-4·83; p=0·024). INTERPRETATION: [18F]FDG-PET-CT was associated with more frequent antimicrobial rationalisation than conventional CT. [18F]FDG-PET-CT can support decision making regarding antimicrobial cessation or de-escalation and should be considered in the management of patients with haematological diseases and persistent or recurrent high-risk neutropenic fever after chemotherapy or transplant conditioning. FUNDING: National Health and Medical Research Council Centre of Research Excellence (APP1116876), Melbourne Health foundation, Gilead Research Fellowship grants supported this study.

Clostridioides difficile infection in paediatric patients with cancer and haematopoietic stem cell transplant recipients.

BACKGROUND: Epidemiology of Clostridioides difficile infection (CDI) in paediatric cancer patients is uncertain. The primary objective was to describe the prevalence of CDI outcomes among paediatric patients receiving cancer treatments. Secondary objectives were to describe clinical features of CDI, propose a definition of severe CDI and to determine risk factors for CDI clinical outcomes. METHODS: A multi-centre retrospective cohort study that included paediatric patients (1-18 years of age) receiving cancer treatments with CDI. Severe CDI definition was achieved by consensus. Univariable and multivariable regression was conducted to evaluate risk factors for CDI outcomes. RESULTS: There were 627 eligible patients who experienced 721 CDI episodes. The prevalence of clinical cure was 82.9%, recurrence was 9.6%, global cure was 75.0% and repeated new CDI episode was 12.8%. The proposed definition of severe CDI was the presence of colitis, pneumatosis intestinalis, pseudomembranous colitis, ileus or surgery for CDI, occurring in 70 (9.7%) episodes. In univariable regression, initial oral metronidazole or initial oral vancomycin were not significantly associated with failure to achieve clinical cure or CDI recurrence. In multiple regression, oral metronidazole was significantly associated with higher odds (odds ratio (OR) 1.7, 95% confidence interval (CI) 1.0-2.7) and oral vancomycin was significantly associated with lower odds (OR 0.4, 95% CI 0.2-0.8) of repeated new episodes. CONCLUSION: The prevalence of clinical cure was 82.9% and recurrence was 9.6% in pediatric patients receiving cancer treatments. Severe CDI, as per our proposed definition, occurred in 9.7% episodes. Initial oral vancomycin was significantly associated with a reduction in repeated new CDI episodes.